Transmission casing



Oct. 11, 1927.

c. R. SHORT TRANSMISSIQN CASING 2 Sheets-Sheet 1 Filed Nov. 24, 1919 2 a a z 514 00 v1 loz file; 9.51mi

a t-to 2 Sheets-Sheet 2 C. R. SHORT TRANsMIss'ION CASING Flled Nov 24 1919 an. em Nm 5 NM Oct. 11, 1927.

Patented Get. 11, 1927.

CHARLES R. SHORT, 015 DETROIT, MICHIGAN, ASSIGNOR TO GENERAL MOTOR-S COR .PORATION, F DETROIT, MICHIGAN, A CORPORATION OF DELAW'ARE.

TRANSMISSION CASING.

Application filed November 24, 1919. Serial No. stoma.

The invention relates to casings of the type generally employed in motor vehicles for enclosing the clutch and gears w th the1r related parts. It is the object of this invention to provide a casing of this type which shall be simpler in construction than those hitherto in use and which can be more cheaply manufactured. With this object in view the invention comprisesbroadly a transmis sion casing whose parts are so proportioned that itmay' be cast without the use of cores and may be Completed with a minimumof machine work. The invention further comprises various details of construction as hereinafter more fully set forth.

The invention also comprises an improved process of manufacture whereby casing constructions of the character mentioned may be produced with a saving'of labor and expense.

In the accompanying drawings which form a part of this specification,

Fig. 1 is a vertical section through the casing showing one embodiment of my invention.

Fig. 2 is an end elevation, and

Fig. 3 is a plan showing a portion of the casing in section. a

In the drawings 1 indicates the casing sec tion within which the clutch and parts of its operating mechanism may be housed, and 2 indicates the gear casing. The clutch casing 1 is designed to be cast in a single piece which may be done without the use of any cores as there are no projecting or overhanging portions such as would prevent the drawing of the pattern. The forward end of this casing is open and is adapted to be secured to an engine crank case of usual form, tapped lugs 3 being provided for this purpose. The rear end of the clutch casing is closed by a diaphragm 4 which is made of sufficient strength to support a main bearing 5 for the transmission shaft 37 and also to provide a bearing 6 for a counter shaft and one or more supports 7 for gear shifting rods. An opening 8 may also be provided by punching out the wall of the casing in order to permit access to the interior.

The gear casing or box 2, shown as of approximately rectangular cross section, is also open at the forward end and closed at the rear and is so shaped as to be cast in a single piece without coring. In order to facilitate the molding operation it will be noted that Ihave so proportioned the parts of the casing'that on the exterior there are no rearward port-ions that overhang any for ward portion, andon the interior conversely, there are no forward portions that overhang ill] a rearward position." The advantages of'this construction from the standpoint of ease and cheapness of manufacture will be obvious to may be so produced.

The casing 2 is provided on top with an opening 9 which may be punched out after the casing as a whole has been. castfThi's opening permits the gear shifting lever 10 to extend inside the casing where it may co-operate with gear shifting mechanism of any desired character. The lever may be mounted as shown in a pressed metal sup port 11 formedwith a depression 12 and cap 13 to co-operate with the ball 14 on the lever. The support 11 may be secured to the gear casing in any desired manner, as by bolts 15 engaging in holes drilled in the casing around the aperture 9.

The rear wall of easing 2 is provided with a recessed portion 16 at the forward end of which is a bearing 17 co-operating with bearing 5 to support the main transmission shaft. This recessed portion also houses a gear 18 adapted to transmit motion to a speedometer drive shaft 19 extending laterally through a bearing 20 which may be supported in a drilled aperture in the enlarged portion 21 of the casing. The rear wall of casing 2 is also provided with a bearing 22 for the end of counter shaft 23, and with one or more supports 24 for gear shifting rods 25. f

lug- 34, and a screw plug 35 is adapted to 7 close said hole. A. drain plug 36 may also be mounted in a thickened portion of the casing wall at the bottom. It will be seen that I have so arranged the thickened or projectingportions providing for thevahave provided flattened portions 38, 89, on

the exterior of easing 2, which flattened portions form convenientseats for the additional housing elements 11 and 31 or any other housing elements which it may be de' s ir able to attach to the gear casing proper. The necessary openings to] cooperate with saidelem ents may be punched out as already mentioned or formed in any other convenile'n t way after the casing hasbeen cast. a The interengaging surfaces of the different casing'elements as ell as the various apertures for bolts or shafts are, of course, machined in the us'ual manner after the casting is otherwise 7 completed.

I'claim; 7 v

1. In transmission mechanism for motor vehic'lesthe combination with a set of speed changing gears and the main transmission shaft thereof of a" casing for said gears having an end wall provided with a recess through which said shaft extendsya' second shaft arranged to extendlaterally from said transmission shaft and means in said recess for driving said second shaft from said transmission shaft; said end Wall being formed withan aperture extending through the material thereof and communicating with'said recess to receive said secondshaft.

2. In transmission mechanism for motor vehicles the combination with a'set of speed changing gears and a transmission shaft,'of a casing for said gears havingan' end wall through which'said'shaft extends said end wall provided with a bearing for said'shaft and a recess surrounding said sha'ft out wardly of sald bearlng, an aperture be ng formed in said casing extending. transverse l to said shaft and comn'iunicatin with said'recess, a speedometer drive shaft in said aperture and means in said. recess for actuatiiig said' drive shaft from said transmission shaft. p p r In testimony whereof I afiiX my signature.

CHARLES asHoRT. 

